Internal thread pitch diameter gauge

Abstract

The utility model discloses a female thread middle diameter size detection pincers, including left jaw, right jaw, thread tooth shape convex side head, thread tooth shape concave side head, tension spring and pin shaft, left jaw middle part and right jaw middle part are hinged together through pin shaft, and the detachable hinged thread tooth shape concave side head has at left jaw front end, and the detachable hinged thread tooth shape convex side head has at right jaw front end, and the thread tooth shape convex side head is connected with the thread tooth shape concave side head through tension spring between. The utility model discloses utilize the pinch to change in shrink, and design rotatable thread tooth shape concave side head and thread tooth shape convex side head at two jaw ends, adopt spring tension mode linear connection thread tooth shape concave side head and thread tooth shape convex side head, and when using, first use standard thread micrometer to adjust the thread middle diameter size, and use the dial gauge to measure the jaw change value, when female thread middle diameter size detection pincers are stretched into the female thread hole, then open the jaw, can measure the female thread's middle diameter value size, and the operation is very convenient.

Description

Technical Field

[0001] This utility model relates to a clamp for measuring the pitch diameter of internal threads. Background Technology

[0002] In machining large-size internal threads (≥M40), the cutting tools and gauges are too large and expensive, making the process cost-effective for small-batch production. Therefore, many machinery manufacturing companies generally use thread turning for machining large-size internal threads in small to medium batches.

[0003] Figure 1 This is a schematic diagram of an internal thread, where P is the pitch, D1 is the minor diameter of the internal thread, D2 is the pitch diameter of the internal thread, and D3 is the major diameter of the internal thread. It is very difficult to measure the pitch diameter of an internal thread because the current national standard thread micrometer can only measure external threads, and the thread plug gauge can only measure the maximum and minimum pitch diameters, and cannot measure the current machining dimension. The operator cannot judge the value of the feed and retraction dimensions and can only judge and control the dimensions based on experience, which can easily cause quality problems. Summary of the Invention

[0004] To solve the above-mentioned technical problems, this utility model provides a simple and easy-to-operate internal thread pitch diameter measuring clamp.

[0005] The technical solution of this utility model to solve the above-mentioned technical problems is: a clamp for measuring the pitch diameter of internal threads, including a left jaw, a right jaw, a threaded convex side head, a threaded concave side head, a tension spring and a pin. The middle part of the left jaw and the middle part of the right jaw are hinged together by the pin. The threaded concave side head is detachably hinged to the front end of the left jaw, and the threaded convex side head is detachably hinged to the front end of the right jaw. The threaded convex side head and the threaded concave side head are connected by a tension spring.

[0006] In the aforementioned internal thread pitch diameter measuring clamp, after the left and right jaws are opened, the convex and concave sides of the thread profile are always perpendicular to the axis of the internal thread.

[0007] The aforementioned internal thread pitch diameter measuring clamp has a dial indicator vertically mounted on the left jaw. The value displayed by the dial indicator is the deviation of the nominal thread pitch diameter.

[0008] The aforementioned internal thread pitch diameter measuring clamp indicates that when the dial indicator displays "0", the current thread pitch diameter value is equal to the nominal thread pitch diameter; when the dial indicator displays "-", the current thread pitch diameter value is less than the nominal thread pitch diameter; and when the dial indicator displays "+", the current thread pitch diameter value is greater than the nominal thread pitch diameter.

[0009] The distance from the hinge point of the left and right jaws to the line connecting the convex and concave sides of the thread profile is L1, and the distance from the hinge point of the left and right jaws to the vertical line of the dial indicator is L2. Therefore, for every n divisions the dial indicator moves, the thread pitch diameter changes by 0.01n*L1 / L2 mm.

[0010] The beneficial effects of this utility model are as follows:

[0011] 1. This utility model utilizes the expansion and contraction of clamps, designing rotatable concave and convex thread profile heads at both jaws. A spring tensioning method is used to linearly connect the concave and convex thread profile heads, ensuring that when the clamps are open, both heads remain perpendicular to the axis of the internal thread. In use, first adjust the thread pitch diameter using a standard thread micrometer, and then measure the jaw expansion using a dial indicator. Once the internal thread pitch diameter measuring clamp is inserted into the internal thread hole, the jaws can be opened to measure the internal thread pitch diameter. The operation is very convenient.

[0012] 2. Both the concave and convex thread profiles of this utility model adopt a detachable hinged design, allowing for the configuration of different thread profiles for different pitches, thus broadening the applicability. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of an internal thread.

[0014] Figure 2 This is a schematic diagram of the structure of this utility model.

[0015] Figure 3 for Figure 2 Enlarged view of part I in the middle.

[0016] Figure 4 This is a schematic diagram of the jaws of this utility model before they open.

[0017] Figure 5 This is a schematic diagram of the jaws of this utility model after they are opened.

[0018] Figure 6 This is a schematic diagram showing how a dial indicator is set to "0" before measurement according to this utility model.

[0019] Figure 7 This is a schematic diagram of the measurement process of this utility model.

[0020] Figure 8 This is a schematic diagram showing the dimensions of a dial indicator. Detailed Implementation

[0021] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0022] like Figures 2-5 As shown, a clamp for measuring the pitch diameter of internal threads includes a left jaw 1, a right jaw 2, a thread profile convex head 3, a thread profile concave head 4, a tension spring 5, and a pin 6. The middle parts of the left jaw 1 and the right jaw 2 are hinged together by the pin 6. The thread profile concave head 4 is detachably hinged to the front end of the left jaw 1, and the thread profile convex head 3 is detachably hinged to the front end of the right jaw 2. The thread profile convex head 3 and the thread profile concave head 4 are connected by the tension spring 5.

[0023] After the left jaw 1 and the right jaw 2 are opened, the thread profile convex head 3 and the thread profile concave head 4 are always perpendicular to the axis of the internal thread.

[0024] A dial indicator 7 is vertically mounted on the left jaw 1. The value displayed by dial indicator 7 is the deviation of the nominal thread pitch diameter. Figure 8 As shown, when dial indicator 7 displays "0" ( Figure 8 When the dial indicator 7 shows a "-" sign (as shown in the middle of the diagram), it means the current thread pitch diameter is equal to the nominal thread pitch diameter; when the dial indicator 7 shows a "-" sign (as shown in the middle of the diagram), it means the current thread pitch diameter is equal to the nominal thread pitch diameter. Figure 8 When the left figure shows a value less than the nominal thread pitch diameter, it means the current thread pitch diameter is less than the nominal thread pitch diameter; when dial indicator 7 shows a "+" position (…), it means the current thread pitch diameter is less than the nominal thread pitch diameter. Figure 8 (See right figure) This means that the current thread pitch diameter is greater than the nominal thread pitch diameter.

[0025] like Figure 4 , Figure 5 As shown, the distance from the hinge point of the left jaw 1 and the right jaw 2 to the line connecting the convex side head 3 and the concave side head 4 of the thread profile is L1, and the distance from the hinge point of the left jaw 1 and the right jaw 2 to the vertical line of the dial indicator 7 is L2. Then, for every n divisions that the dial indicator 7 moves, the thread pitch diameter changes by 0.01n*L1 / L2 mm.

[0026] This invention utilizes the opening and closing of the clamps, and designs rotatable threaded concave side head 4 and threaded convex side head 3 at the two jaws. The threaded concave side head 4 and threaded convex side head 3 are connected in a straight line by a spring tensioning method, so that when the clamps are opened, the threaded concave side head 4 and threaded convex side head 3 are always perpendicular to the axis of the internal thread.

[0027] When using, install the corresponding thread profile concave side head 4, thread profile convex side head 3, and tension spring 5. First, use a standard thread micrometer 8 to adjust the thread pitch diameter (e.g., Figure 6 As shown, use dial indicator 7 to "lock" the dimension (adjust to "0") to check the dimension; when the internal thread pitch diameter measuring pliers are inserted into the internal thread hole, open the jaws so that the concave side head 4 and the convex side head 3 of the thread profile symmetrically contact the product tooth surface, and the pitch diameter value of the internal thread can be measured. The operation is very convenient.

Claims

1. A clamp for measuring the pitch diameter of internal threads, characterized in that: It includes a left jaw, a right jaw, a threaded convex head, a threaded concave head, a tension spring, and a pin. The middle parts of the left jaw and the right jaw are hinged together by the pin. The front end of the left jaw is detachably hinged to a threaded concave head, and the front end of the right jaw is detachably hinged to a threaded convex head. The threaded convex head and the threaded concave head are connected by a tension spring.

2. The internal thread pitch diameter measuring clamp according to claim 1, characterized in that: After the left and right jaws are opened, the convex and concave sides of the thread profile are always perpendicular to the axis of the internal thread.

3. The internal thread pitch diameter measuring clamp according to claim 1, characterized in that: A dial indicator is vertically mounted on the left jaw, and the value displayed by the dial indicator is the deviation of the nominal thread pitch diameter.

4. The internal thread pitch diameter measuring clamp according to claim 3, characterized in that: When the dial indicator displays "0", it means that the current thread pitch diameter is equal to the nominal thread pitch diameter; when the dial indicator displays "-", it means that the current thread pitch diameter is less than the nominal thread pitch diameter; when the dial indicator displays "+", it means that the current thread pitch diameter is greater than the nominal thread pitch diameter.

5. The internal thread pitch diameter measuring clamp according to claim 4, characterized in that: The distance from the hinge point of the left and right jaws to the line connecting the convex and concave sides of the thread profile is L1, and the distance from the hinge point of the left and right jaws to the vertical line of the dial indicator is L2. Then, for every n divisions the dial indicator moves, the thread pitch diameter changes by 0.01n*L1 / L2 mm.

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